RAD51 Inhibitor B02 (B02) is an inhibitor of human RAD51 with an IC₅₀ of 27.4 μM. IC50 & Target: IC50: 27.4 μM (hRAD51)^[1] In Vitro: RAD51 Inhibitor B02 specifically inhibits human RAD51 (IC₅₀=27.4 μM), but not its E. coli homologue RecA (IC₅₀>250 μM)^[1]. The combination of B02 with cisplatin has the strongest killing effect on the human breast cancer cells MDA-MB-231^[2]. In Vivo: B02 significantly enhances the therapeutic effect of cisplatin on tumor cells in vivo. B02 is tolerated by mice at doses up to 50 mg/kg without obvious body weight loss. No inhibition of tumor growth is observed on mice solely treated by B02. Mice treated with 4 mg/kg cisplatin, however, shows a 33% inhibition of tumor growth. Finally, mice treated with 50 mg/kg B02 and 4 mg/kg cisplatin shows a 66% inhibition of tumor growth^[2].